2 * metadata/gc-internals.h: Internal GC interface
4 * Author: Paolo Molaro <lupus@ximian.com>
6 * (C) 2002 Ximian, Inc.
7 * Copyright 2012 Xamarin Inc (http://www.xamarin.com)
8 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
11 #ifndef __MONO_METADATA_GC_INTERNAL_H__
12 #define __MONO_METADATA_GC_INTERNAL_H__
15 #include <mono/utils/gc_wrapper.h>
16 #include <mono/metadata/object-internals.h>
17 #include <mono/metadata/threads-types.h>
18 #include <mono/sgen/gc-internal-agnostic.h>
19 #include <mono/utils/gc_wrapper.h>
21 #define mono_domain_finalizers_lock(domain) mono_os_mutex_lock (&(domain)->finalizable_objects_hash_lock);
22 #define mono_domain_finalizers_unlock(domain) mono_os_mutex_unlock (&(domain)->finalizable_objects_hash_lock);
24 /* Register a memory area as a conservatively scanned GC root */
25 #define MONO_GC_REGISTER_ROOT_PINNING(x,src,msg) mono_gc_register_root ((char*)&(x), sizeof(x), MONO_GC_DESCRIPTOR_NULL, (src), (msg))
27 #define MONO_GC_UNREGISTER_ROOT(x) mono_gc_deregister_root ((char*)&(x))
30 * Register a memory location as a root pointing to memory allocated using
31 * mono_gc_alloc_fixed (). This includes MonoGHashTable.
33 /* The result of alloc_fixed () is not GC tracked memory */
34 #define MONO_GC_REGISTER_ROOT_FIXED(x,src,msg) do { \
35 if (!mono_gc_is_moving ()) \
36 MONO_GC_REGISTER_ROOT_PINNING ((x),(src),(msg)); \
40 * Return a GC descriptor for an array containing N pointers to memory allocated
41 * by mono_gc_alloc_fixed ().
43 /* For SGEN, the result of alloc_fixed () is not GC tracked memory */
44 #define MONO_GC_ROOT_DESCR_FOR_FIXED(n) (mono_gc_is_moving () ? mono_gc_make_root_descr_all_refs (0) : MONO_GC_DESCRIPTOR_NULL)
46 /* Register a memory location holding a single object reference as a GC root */
47 #define MONO_GC_REGISTER_ROOT_SINGLE(x,src,msg) do { \
48 g_assert (sizeof (x) == sizeof (MonoObject*)); \
49 mono_gc_register_root ((char*)&(x), sizeof(MonoObject*), mono_gc_make_root_descr_all_refs (1), (src), (msg)); \
53 * This is used for fields which point to objects which are kept alive by other references
56 #define MONO_GC_REGISTER_ROOT_IF_MOVING(x,src,msg) do { \
57 if (mono_gc_is_moving ()) \
58 MONO_GC_REGISTER_ROOT_SINGLE(x,src,msg); \
61 #define MONO_GC_UNREGISTER_ROOT_IF_MOVING(x) do { \
62 if (mono_gc_is_moving ()) \
63 MONO_GC_UNREGISTER_ROOT (x); \
66 /* useful until we keep track of gc-references in corlib etc. */
67 #define IS_GC_REFERENCE(class,t) (mono_gc_is_moving () ? FALSE : ((t)->type == MONO_TYPE_U && (class)->image == mono_defaults.corlib))
69 void mono_object_register_finalizer (MonoObject *obj);
70 void ves_icall_System_GC_InternalCollect (int generation);
71 gint64 ves_icall_System_GC_GetTotalMemory (MonoBoolean forceCollection);
72 void ves_icall_System_GC_KeepAlive (MonoObject *obj);
73 void ves_icall_System_GC_ReRegisterForFinalize (MonoObject *obj);
74 void ves_icall_System_GC_SuppressFinalize (MonoObject *obj);
75 void ves_icall_System_GC_WaitForPendingFinalizers (void);
77 MonoObject *ves_icall_System_GCHandle_GetTarget (guint32 handle);
78 guint32 ves_icall_System_GCHandle_GetTargetHandle (MonoObject *obj, guint32 handle, gint32 type);
79 void ves_icall_System_GCHandle_FreeHandle (guint32 handle);
80 gpointer ves_icall_System_GCHandle_GetAddrOfPinnedObject (guint32 handle);
81 void ves_icall_System_GC_register_ephemeron_array (MonoObject *array);
82 MonoObject *ves_icall_System_GC_get_ephemeron_tombstone (void);
85 extern void mono_gc_init (void);
86 extern void mono_gc_base_init (void);
87 extern void mono_gc_cleanup (void);
88 extern void mono_gc_base_cleanup (void);
91 * Return whenever the current thread is registered with the GC (i.e. started
92 * by the GC pthread wrappers on unix.
94 extern gboolean mono_gc_is_gc_thread (void);
96 extern gboolean mono_gc_is_finalizer_internal_thread (MonoInternalThread *thread);
98 extern void mono_gc_set_stack_end (void *stack_end);
100 /* only valid after the RECLAIM_START GC event and before RECLAIM_END
101 * Not exported in public headers, but can be linked to (unsupported).
103 gboolean mono_object_is_alive (MonoObject* obj);
104 gboolean mono_gc_is_finalizer_thread (MonoThread *thread);
105 gpointer mono_gc_out_of_memory (size_t size);
106 void mono_gc_enable_events (void);
107 void mono_gc_enable_alloc_events (void);
109 void mono_gchandle_set_target (guint32 gchandle, MonoObject *obj);
111 /*Ephemeron functionality. Sgen only*/
112 gboolean mono_gc_ephemeron_array_add (MonoObject *obj);
115 mono_gc_GCHandle_CheckCurrentDomain (guint32 gchandle);
117 /* User defined marking function */
118 /* It should work like this:
119 * foreach (ref in GC references in the are structure pointed to by ADDR)
122 typedef void (*MonoGCMarkFunc) (MonoObject **addr, void *gc_data);
123 typedef void (*MonoGCRootMarkFunc) (void *addr, MonoGCMarkFunc mark_func, void *gc_data);
125 /* Create a descriptor with a user defined marking function */
126 MonoGCDescriptor mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker);
128 /* Return whenever user defined marking functions are supported */
129 gboolean mono_gc_user_markers_supported (void);
131 /* desc is the result from mono_gc_make_descr*. A NULL value means
132 * all the words might contain GC pointers.
133 * The memory is non-moving and it will be explicitly deallocated.
134 * size bytes will be available from the returned address (ie, descr
135 * must not be stored in the returned memory)
136 * NOTE: Under Boehm, this returns memory allocated using GC_malloc, so the result should
137 * be stored into a location registered using MONO_GC_REGISTER_ROOT_FIXED ().
139 void* mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg);
140 void mono_gc_free_fixed (void* addr);
142 /* make sure the gchandle was allocated for an object in domain */
143 gboolean mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain);
144 void mono_gchandle_free_domain (MonoDomain *domain);
146 typedef void (*FinalizerThreadCallback) (gpointer user_data);
148 /* if there are finalizers to run, run them. Returns the number of finalizers run */
149 gboolean mono_gc_pending_finalizers (void);
150 void mono_gc_finalize_notify (void);
152 void* mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size);
153 void* mono_gc_alloc_obj (MonoVTable *vtable, size_t size);
154 void* mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length);
155 void* mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size);
156 void* mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len);
157 void* mono_gc_alloc_mature (MonoVTable *vtable, size_t size);
158 MonoGCDescriptor mono_gc_make_descr_for_string (gsize *bitmap, int numbits);
160 void mono_gc_register_for_finalization (MonoObject *obj, void *user_data);
161 void mono_gc_add_memory_pressure (gint64 value);
162 MONO_API int mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg);
163 void mono_gc_deregister_root (char* addr);
164 void mono_gc_finalize_domain (MonoDomain *domain);
165 void mono_gc_run_finalize (void *obj, void *data);
166 void mono_gc_clear_domain (MonoDomain * domain);
167 /* Signal early termination of finalizer processing inside the gc */
168 void mono_gc_suspend_finalizers (void);
172 * Register a root which can only be written using a write barrier.
173 * Writes to the root must be done using a write barrier (MONO_ROOT_SETREF).
174 * If the root uses an user defined mark routine, the writes are not required to be
175 * to the area between START and START+SIZE.
176 * The write barrier allows the GC to avoid scanning this root at each collection, so it
178 * FIXME: Add an API for clearing remset entries if a root with a user defined
179 * mark routine is deleted.
181 int mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg);
183 void mono_gc_wbarrier_set_root (gpointer ptr, MonoObject *value);
185 /* Set a field of a root registered using mono_gc_register_root_wbarrier () */
186 #define MONO_ROOT_SETREF(s,fieldname,value) do { \
187 mono_gc_wbarrier_set_root (&((s)->fieldname), (MonoObject*)value); \
190 void mono_gc_finalize_threadpool_threads (void);
192 /* fast allocation support */
195 // Regular fast path allocator.
196 MANAGED_ALLOCATOR_REGULAR,
197 // Managed allocator that just calls into the runtime. Used when allocation profiling w/ AOT.
198 MANAGED_ALLOCATOR_SLOW_PATH,
199 } ManagedAllocatorVariant;
201 int mono_gc_get_aligned_size_for_allocator (int size);
202 MonoMethod* mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size);
203 MonoMethod* mono_gc_get_managed_array_allocator (MonoClass *klass);
204 MonoMethod *mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant);
206 guint32 mono_gc_get_managed_allocator_types (void);
208 /* Return a short string identifying the GC, indented to be saved in AOT images */
209 const char *mono_gc_get_gc_name (void);
211 /* Fast write barriers */
212 MonoMethod* mono_gc_get_specific_write_barrier (gboolean is_concurrent);
213 MonoMethod* mono_gc_get_write_barrier (void);
215 /* Fast valuetype copy */
216 void mono_gc_wbarrier_value_copy_bitmap (gpointer dest, gpointer src, int size, unsigned bitmap);
218 /* helper for the managed alloc support */
220 ves_icall_string_alloc (int length);
223 * Functions supplied by the runtime and called by the GC. Currently only used
228 * Function called during thread startup/attach to allocate thread-local data
229 * needed by the other functions.
231 gpointer (*thread_attach_func) (void);
233 * Function called during thread deatch to free the data allocated by
234 * thread_attach_func.
236 void (*thread_detach_func) (gpointer user_data);
238 * Function called from every thread when suspending for GC. It can save
239 * data needed for marking from thread stacks. user_data is the data returned
240 * by attach_func. This might called with GC locks held and the word stopped,
241 * so it shouldn't do any synchronization etc.
243 void (*thread_suspend_func) (gpointer user_data, void *sigcontext, MonoContext *ctx);
245 * Function called to mark from thread stacks. user_data is the data returned
246 * by attach_func. This is called twice, with the word stopped:
247 * - in the first pass, it should mark areas of the stack using
248 * conservative marking by calling mono_gc_conservatively_scan_area ().
249 * - in the second pass, it should mark the remaining areas of the stack
250 * using precise marking by calling mono_gc_scan_object ().
252 void (*thread_mark_func) (gpointer user_data, guint8 *stack_start, guint8 *stack_end, gboolean precise, void *gc_data);
254 * Function called for debugging to get the current managed method for
255 * tracking the provenances of objects.
257 gpointer (*get_provenance_func) (void);
260 /* Set the callback functions callable by the GC */
261 void mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks);
262 MonoGCCallbacks *mono_gc_get_gc_callbacks (void);
264 /* Functions callable from the thread mark func */
266 /* Scan the memory area between START and END conservatively */
267 void mono_gc_conservatively_scan_area (void *start, void *end);
269 /* Scan OBJ, returning its new address */
270 void *mono_gc_scan_object (void *obj, void *gc_data);
272 /* Return the suspend signal number used by the GC to suspend threads,
273 or -1 if not applicable. */
274 int mono_gc_get_suspend_signal (void);
276 /* Return the suspend signal number used by the GC to suspend threads,
277 or -1 if not applicable. */
278 int mono_gc_get_restart_signal (void);
281 * Return a human readable description of the GC in malloc-ed memory.
283 char* mono_gc_get_description (void);
286 * Configure the GC to desktop mode
288 void mono_gc_set_desktop_mode (void);
291 * Return whenever this GC can move objects
293 gboolean mono_gc_is_moving (void);
295 typedef void* (*MonoGCLockedCallbackFunc) (void *data);
297 void* mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data);
299 int mono_gc_get_los_limit (void);
301 guint8* mono_gc_get_card_table (int *shift_bits, gpointer *card_mask);
302 gboolean mono_gc_card_table_nursery_check (void);
304 void* mono_gc_get_nursery (int *shift_bits, size_t *size);
306 void mono_gc_set_current_thread_appdomain (MonoDomain *domain);
308 void mono_gc_set_skip_thread (gboolean skip);
311 int mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg);
315 * Return whenever GC is disabled
317 gboolean mono_gc_is_disabled (void);
320 * Return whenever this is the null GC
322 gboolean mono_gc_is_null (void);
324 void mono_gc_set_string_length (MonoString *str, gint32 new_length);
326 #if defined(__MACH__)
327 void mono_gc_register_mach_exception_thread (pthread_t thread);
328 pthread_t mono_gc_get_mach_exception_thread (void);
331 gboolean mono_gc_precise_stack_mark_enabled (void);
333 typedef struct _RefQueueEntry RefQueueEntry;
335 struct _RefQueueEntry {
343 struct _MonoReferenceQueue {
344 RefQueueEntry *queue;
345 mono_reference_queue_callback callback;
346 MonoReferenceQueue *next;
347 gboolean should_be_deleted;
351 MONO_GC_FINALIZER_EXTENSION_VERSION = 1,
356 gboolean (*is_class_finalization_aware) (MonoClass *klass);
357 void (*object_queued_for_finalization) (MonoObject *object);
358 } MonoGCFinalizerCallbacks;
360 MONO_API void mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks);
364 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved);
367 guint mono_gc_get_vtable_bits (MonoClass *klass);
369 void mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size);
371 /* If set, print debugging messages around finalizers. */
372 extern gboolean log_finalizers;
374 /* If set, do not run finalizers. */
375 extern gboolean mono_do_not_finalize;
376 /* List of names of classes not to finalize. */
377 extern gchar **mono_do_not_finalize_class_names;
379 #endif /* __MONO_METADATA_GC_INTERNAL_H__ */